Idiopathic Pulmonary Fibrosis (IPF) is a serious and progressively debilitating illness wherein inflammation of lung alveoli and airways leads to permanent fibrosis and respiratory impairment. IPF affects primarily middle aged and older adults, with a median survival of only 3 to 5 years. The New Mexico Interstitial Lung Disease (ILD) registry, a study designed to describe the prevalence and incidence of ILDs in a population-based cohort, found the prevalence and incidence of IPF to be as much as ten times greater than previously estimated, and demographic changes suggest that the prevalence of IPF will increase. In spite of the severity and impact of this illness, little is known about prognostic indicators for IPF, and even less is known about how corticosteroid treatment affects survival or quality of life. In this NHLBI Mentored Clinical Scientist Development Award proposal, the applicant plans to use the New Mexico ILD registry to identify clinical, pathophysiologic, and socioeconomic factors associated with improved prognosis in IPF, and examine the effects of corticosteroid therapy on survival and quality of life. The ILD registry is maintained jointly by members of the Epidemiology Division of the University of New Mexico, and the New Mexico Tumor Registry. In the first phase of this study, the 202 incident cases of IPF identified between 10/l/88 to 9/30/92 will be reviewed, and factors associated with long-term survival and improved quality of life in this cohort identified. Quality of life will be measured using standardized quality of well-being assessment tools, and corticosteroid effects will be measured after adjustment for confounding factors. Survival and quality of life influences will then be modeled prospectively by reopening the New Mexico IPF registry to new incident IPF cases. At the conclusion of this study, we will be able to identify the important prognostic factors in short-term and long-term survivors of IPF, construct models of the relative significance of each of these factors, and describe how corticosteroids influence survival and quality of life. The New Mexico ILD registry will provide unique information on IPF prognosis in a population-based cohort and new information on the contribution of socioeconomic factors. This project will provide its principal investigator, Douglas W. Mapel MD, necessary resources and experience to achieve his goal of becoming an independent investigator in pulmonary epidemiology and outcomes research.